DE1050945B - - Google Patents

Description

The process is used for the solvent extraction of petroleum using lactones, preferably Butyrolactone, as a solvent.

It is known that aliphatic lactones have selective solvency for acetylene and for extraction this component can be used from gas mixtures.

It has been found that lactones, especially butyrolactone, also aromatics and olefins, metal-containing impurities, Selectively dissolve aromatics with condensed rings as well as nitrogen compounds that are present in liquid Hydrocarbon fractions are included. These lactones can therefore be used to remunerate various petroleum fractions can be used by extraction, both in the extractive removal more harmful Components as well as the extractive extraction of high-quality components in concentrated form.

The method therefore comprises various embodiments. Once it succeeds with lactones the mentioned To remove substances from high-boiling petroleum fractions and use them for catalytic cleavage To make it much more suitable, on the other hand aromatic and / or olefinic hydrocarbons be concentrated in the boiling range of motor fuels in order to increase the octane number.

Another possibility is the production of lubricating oils with a high viscosity index by extraction of lubricating oil distillates with lactones.

Finally, the same procedure can also be used to determine the smoke point of the luminous oil by extraction improve the aromatic components and increase their cetane number by extracting diesel fuels.

The pretreatment of high-boiling gas oil fractions, which are intended for catalytic cleavage, is important. Up until now, the fractions of the crude oil boiling above the gas oil range had to go up together with the residue Asphalt, fuel oil and other low-value products are processed because they contain significant amounts of metal compounds (Nickel, vanadium and iron) contain, which poison the cracking catalyst, so that during the cracking Under certain circumstances there is such a strong hydrogen evolution that the gas compressors as a result of the change the gas density no longer work properly.

As already mentioned, these metal-containing impurities can be selectively obtained by extraction with butyrolactone remove, so that you get the high-boiling petroleum fractions that are previously processed on low-value products had to lead to the catalytic cleavage. Since the lactones also have a selective dissolving power for Aromatics with condensed rings and nitrogen compounds are also found in the high-boiling ones Petroleum fractions occur and a disadvantageous we-process for the decomposition of petroleum

Applicant:

Esso Research and Engineering Company, Elizabeth, N.J. (V. St. A.)

Representative: E. Maemecke, Berlin-Lichterfelde West,
and Dr. W. Kühl, Hamburg 36, Esplanade 36 a,
Patent attorneys

Claimed priority: V. St. v. America March 1 and December 22, 1955

Effect on the cleavage process can be achieved by pretreating these fractions with lactones at the same time their removal along with the metal connections.

The cause of this unusual dissolving power of the lactones is still unclear. Anyway, behaves Butyrolactone as a solvent in the context of the invention is completely different from the previously known selective solvents, such as B. furfural.

Solubility regulators (e.g. water, aliphatic alcohols, acetic acid) can be used for certain forms of application and ethylene glycol) in addition to lactones such as butyrolactone, which reduce the selective dissolution behavior of the Do not significantly change lactones, but rather influence the oil solubility of the lactones. Solubility regulators are suitable especially for the extraction with butyrolactone

809 750/452

1 050

945

higher temperatures. They can along with metal impurities, nitrogen compounds and aro-butyrolactone (less than a third of the total matic compounds with condensed rings far solvent mixture) be used. going liberated, better behavior in splitting.

Solvent extractions with butyrolactone are carried out in zone 14 catalytically at from 27 to 260 ° C. in the usual manner. The selectivity is split by 5. The temperature from fractionation column 1 is not decisively influenced by Leidie; The light gas oil fraction withdrawn from preference 5 can therefore be carried out immediately, and therefore at moderate temperatures, in order to be fed to the cracking plant 14; But you can also keep the charge on a suitable treatment in whole or in part with the heavy gas oil in the viscosity. The range from about 38 to 93 ° C extraction zone 8 can be extracted. Appropriate is preferred. The extraction pressure can fluctuate within io if the heavy gas oil is mixed with a smaller amount and wider limits (approx. 1 to 51 at), but since it does not play a special role in light gas oil, the viscosity of the gas oil is usually reduced if desired ,
at atmospheric pressure.

The amount of solvent mixture used in Example 1
varies somewhat with the feed 15 to be treated

good and the desired efficiency. In general, heavy gas oil boiling 50% to 510 ° C, its

if it is 0.5 to 3 parts by volume of solvent per part of volume boiling point is above 595 ° C and that before loading

Oil, for most uses, is a negotiation of 2.3 parts nickel and 0.2 parts vanadium each

ratio of about 1: 1 preferred. Million contained was made with paragraphs in three stages

The solvent extraction with lactones takes place after 20 butyrolactone extracts, with 1 part by volume of lactone each

known method, the solvent is from the oil volume per stage at 82 ° C and atmospheric pressure

Raffinate and the extract was applied back in the usual way. The individual approaches were 5 min

won. utes mechanically stirred and then 5 to 10 minutes

The procedure is generally left to the extraction by itself. The yield of raffinate was by gas oils applicable, boiling at 230-705 ° C, nament- 25 stripping of the solvent 87 ° / _0th After treating on fractions that boil above 480 to 510 ° C. As a result, the oil only contained 0.25 parts nickel per million and, since these are particularly rich in metal impurities, no vanadium. For the production of the feed material for the impurities from heavy gas oils with the achievement of catalytic cleavage, it is particularly advisable to remove the part of the feed that is above high yields largely to completely, to separate off about 510 ° C. 30 Comparative experiments with phenol and an additive from and to extract. gave some water to regulate the oil solubility

1 serves to explain the production of a significantly poorer result. The yield at

Dispatch for catalytic cleavage. Extraction down to the same nickel content was only

A fractionator 1 of conventional design is used for the 72%, the extraction with furfural to a content separation of the crude oil into fractions of different 35 of 0.25 parts nickel per million yielded only 77% of oil. Boiling range. Crude oil is introduced into the frac-butyrolactone through line 2 , which is a very effective means of the ionizing tower. C ₄ and lighter gases draw a substantial reduction in the nickel content and are released overhead through line 3 ; a gasoline fraction is taken off as a side stream through line 4 , far higher yields than the usual extraction. With solvents such as phenol or furfural.
Line 5 is preferably light gas oil boiling from 40
range from about 230 to 510 ° C removed as a higher-boiling side stream. The highest-boiling side stream, example 2
heavy gas oil (boiling points of 510 and 705 ° C) flows

through line 6 . Heavy residual oil is removed from heavy gas oil according to Example 1 with a Ge bottom through line 7. 45 mix of 90% butyrolactone and 10% water at 82 ° C. The heavy gas oil fraction that repeatedly extracts metal impurities in batches. This mixture resulted in a considerable amount, from line 6 the same yield as 100% lactone enters through line 9 with the same reduction in the nickel content (0.25 to solvent extraction in tower 8. Butyro- l.O parts per million) and flows in the lactone.
Tower 8 towards the heavy gas oil. The extraction 50

can e.g. B. at 65 ° C and atmospheric pressure with about Example 3
1 part of butyrolactone per part of heavy gas oil

are executed. The raffinate (treated oil and small amounts of thin the heavy oil with 2 parts by volume of a light butyrolactone) is removed overhead through line 10. 55 Hydrocarbon fraction (C ₇ ) with butyrolactone ex-residue solvent can be tracted in a stripping zone 11. Three intermittently performed extractions are withdrawn overhead from the treated oil; tions followed by stripping of the dilution In this case, the deposited butyrolactone by means of managerial resulted in a yield of 94 weight percent tung 12 is removed, and returns in circulation through conduit 9 of refined oil having a nickel content of 0.49 parts of the tower 8 back. The desolventized oil 60 per million. The yield is 13% higher than when it flows through line 13 to the catalytic cleavage zone 14. Phenol extraction to the same nickel content.

The extract flowing off from tower 8 through line 15
can be treated in a similar manner in a solvent scraper 16 , from the butyrolactone example 4
subtracts overhead through line 17. An extract oil 65

flows from the bottom of the scraper 16 through line 18 to add other solvent properties to the lactones

away; It can be blended with fuel oil or investigated for the extraction of various nitrogen compounds

processed by chemicals. containing hydrocarbon oils with butyrolactone ex-

The treated oil, which is tracted through line 13 to. The starting oils and extraction results are

catalytic cleavage shows, as it is compiled from the 70 in the table below.

5 6

Table I

Extraction of nitrogen compounds from oils

attempt oil solvent number of
Extractions temperature
° C A. Raw Colorado
Shale oil
the same 90 ° / ₀ butyrolactone
+ 10% water 1 35 B. Partially hydrogenated
Shale oil
the same Butyrolactone 1 35 C. El Segundo
Heavy gas oil
the same
the same Butyrolactone
90% butyrolactone
+ 10% water 1
2 40.5
40.5

Raffinate yield Io

'/ o N ₂

89

95

83 89

Butyrolactone is therefore also a selective solution - 85% of the nickel impurities were

Medium for the 25 vanadium compounds found in the starting oils removed to 100%, the content

Nitrogen compounds. The extraction of the heavy nitrogen compounds was increased from 0.38 to 0.20% Gas oil with butyrolactone provided a yield of 83%; degraded.

Example 5

To the versatile effects of butyrolactone as
To demonstrate solvent, a heavy catalytic return oil (boiling range about 370 to 540 ° C) was used
treated about 260% butyrolactone. These oils boiling above the boiling range of distillate fuel oil and 35 shows the table below, are obtained from various oil mixtures,

contain, as has recently been found, considerable amounts of high quality lubricating oil components. The catalytic one Return oil was batch treated at 93 ° C and atmospheric pressure. The test results

Table II

Multi-stage batch extraction of heavy catalytic return oil

Temperature 93.3 ° C; Atmospheric pressure

attempt
No. Volume percentage of the
Solvent
all in all yield
Weight
percent Specific
weight Viscose
37.8 ° Raffinate
did, cSt
98.9 ° Viscosity
index Viscosity
Density constant feed O 0.953 21.38 3.8 59.1 0.926

Butyrolactone as a solvent

1 100 57.7 0.860 13.45 3.32 127.8 0.821 2 165 42.5 0.847 13.05 3.35 141.2 0.806 3 216 39.9 0.837 13.05 0.795 4th 262 39.0 0.834 12.84 3.35 145.2 0.791 90% phenol + 10% water as a solvent 1 100 54.6 0.904 9.8 * 3.65 93.0 0.870 2 168 39.5 0.863 8.91 * 3.55 128.0 0.822 3 216 34.5 0.845 8.3 * 3.42 136.0 0.803 4th 257 29.3 0.839 8.2 * 3.42 144.0 0.797

* At 55 ° C

The extraction with butyrolactone was carried out 65 in order to effectively remove undesirable lubricating oil components and to obtain high quality lubricating oil of high viscosity index. A comparison of the extraction results with those using phenol is particularly interesting. In this case it was 70

Yield of equivalent lubricating oil (viscosity index 140) only 73% of that when using the one according to the invention Process achieved value. Needed to achieve a certain improvement in the viscosity index you get much less butyrolactone than phenol. These comparative values are shown in the following table.

Table III

Comparison of the efficacies of butyrolactone and one consisting of 90% phenol and 10% water Extractants

Volume percent solvent
needed

Butyrolactone

0
45
70
105

90 ° / ₀ sodium phenol

0
100
140
190

To achieve a viscosity index of

59 (feed) 100 115 130

The process is therefore very versatile and technically important for improving petroleum fractions in the Boiling range of the gas oil, especially for the production of the starting material for catalytic cleavage and higher quality Lubricating oils.

According to another embodiment, lactones are used to concentrate those boiling in the gasoline range Aromatics and / or olefins are used. The great resistance and high selectivity make lactones, especially butyrolactone, particularly suitable for this, in the extraction of gas oils they are used in relatively pure form or in a mixture with other solubility regulators.

Mixtures of aromatics and non-aromatics can be extracted with lactones at 10 to 150 ° C and 1 to 27 atm and broken down into an extract and raffinate phase. Aromatics and olefins are dissolved in the extract, the Raffinate contains the non-aromatics.

y-Butyrolactone is particularly suitable for the enrichment of aromatics in reformates, which makes their Octane number is significantly improved.

2 shows a hydroforming plant in which DestiDatbenzin (boiling range 90 to 165 ° C.) passes via line 20 and hydrogen via line 24 into the hydroforming chamber 22 , which is operated in the usual way. The hydroformate flows via line 26 into the distillation zone 28, from which the C ₄ and lighter hydrocarbons are drawn off at the top through pipe 36 . The C ₅ fraction, which is taken off as a side stream, is expediently separated off before the solvent extraction and combined again with the extract via line 34. The C _e ⁺ hydroformates are fed via line 32 to zone 30 for the solvent extraction, where they are treated with γ-butyrolactone as described for the extraction of the gas oil fractions. According to the present process, the raffinate, which was previously the desired product, is preferably recycled for hydroforming and further conversion into aromatics. The extract containing the aromatics is separated from the solvent, withdrawn through line 40 and combined with the C ₅ hydrocarbons which were previously separated to form a C ₆ ⁺ gasoline of high octane number. Butyrolactone can also be used to advantage for the extraction of the products of thermal or catalytic cracking, which contain considerable amounts of high octane olefins. Butyrolactone is particularly suitable for treating olefin-containing feeds which heretofore could not be treated with conventional solvents such as sulfur dioxide.

Example 6

In order to show the high selectivity of lactones as extractants for aromatics, a mixture of Equal parts of n-heptane and toluene with γ-butyrolactone and extracted with / S-propiolactone at 27.degree. Comparatively extraction experiments were carried out with diethylene glycol, a preferred commercial solvent for this purpose, carried out. The investigations were carried out by means of a single extraction. Butyrolactone is highly selective and significantly superior to glycol. The solvency of γ-butyrolactone is as shown below Table shows incomparably higher.

30 Table IV
Comparison of the dissolving power
Single extraction with undiluted solvents

35

40 "/" toluene

in the
Raffinate

15th
25th
35

Amount of solvent,
Percentage by volume of the toluene-heptane mixture

y-butyrolactone / Ϊ-propiolactone diethylene glycol

200
110
55

265
150
80

> 1500
640
280

^ -Propiolactone is therefore also highly selective, albeit with a slightly lower solvent capacity. the Outstanding properties of these lactones can be seen from the table above and from Table V in detail.

Table V

Use of solvents for the discontinuous extraction of aromatics at 27 ° C Charge: toluene-heptane mixture in a volume ratio of 50:50

Solvent*

Solvent to oil ratio

Refractive index at 26 ° C

Raffinate toluene concentrates
tration
Volume percentage

yield

Volume percentage

Refractive index at
26 ° C

extract

Toluene concentrations
tration
Volume percentage

yield

Volume percentage

100% butyrolactone ...
100% butyrolactone ...
100% butyrolactone ...

95% butyrolactone. ..

85% butyrolactone ...

75% butyrolactone ...
100% / 3-propiolactone ..
100% diethylene glycol
100% diethylene glycol
100% diethylene glycol

90% diethylene glycol

85% diethylene glycol

1 2 2 2 2 2 1 2 4 8 2 2

1.4128 1.4025 1.4030 1.4078 1.4180 1.4261 1.4061 1.4270 1.4184 1.4096 1.4325 1.4338

26th
15th
15th
20th
30th
38
20th
39
30th
23
44
45

52
37
40
52
68
79
50
80
67
53
89
91

1.4650
1.4588
1.4610
1.4706
1.4797
1.4837
1.4680
1.4808
1.4770
1.4700
1.4848
1.4807

74
70
71
81
89
93
79
90
87
80
94
90

48
63
60
48
32
21
50
20th
33
47
11
9

* Less than 100 ° / ₀ sodium solvents are diluted with water.

10

Example 7

A hydroformat (research octane number 87.8) was freed from pentane; the C ₆ ⁺ fraction (research octane number 89.8) was extracted in a continuous multi-stage extraction unit. Water was introduced to control hydrocarbon solubility. Comparative extraction tests on hydroformate with butyrolactone and diethylene glycol show that the most effective separation of aromatics from non-aromatics takes place by extraction with butyrolactone. The high dissolving power, which was determined in preliminary tests with the lactone, was confirmed in the continuous extraction in the multi-stage process. Diethylene glycol is less selective and therefore requires a higher solvent to oil ratio.

solvent

Extract yield (octane number 100), volume percentage of the extracted C ₆ ⁺ fraction ...

Solvent-to-oil ratio of 50 ° / ₀ yield strength extract

Butyrolactone + 7.5% H ₂ O

71

1.5

Diethylene glycol

43

7.5

Table VI provides more detailed information on the extraction.

Table VI

Solvent extraction of C _e ⁺ hydroformate in multi-stage extraction at 27 ° C

Butyrolactone Diethylene glycol

Water addition, ° / ₀

Solvent to oil ratio.

Extract:

Yield, percent by volume.

Research Octane Number

Refractive index at 26 ° C.

Raffinate:

Yield, percent by volume.

Research Octane Number

Refractive index at 26 ° C. specific weight

ASTM distillation, ° C

Start of boiling

5%

10 ° /,

20%

30%

40%

50%

60%

70%

80%

90%

95%

End of boiling

Distillate,%

Residue, %

89.8
1.4535
0.8044

97.2
104.4
107.2
111.7
115.6
121.1
125.6
127.2
139.4
148.3
159.4
170.0
196.1

98.5
1.0

7.5 2

66

100.6 1.4812

34

36.2 1.3992 0.7186

96.1 102.2 103.9 106.7 108.9 112.2 115.0 118.9 123.3 130.0 140.0 148.9 167.8

98.5 1.0

0 4

33

101.2 1.4873

67

72.8 1.4366 0.7792

96.7 105.0 108.9 113.3 116.7 120.6 125.0 130.6 136.7 144.4 155.6 165.6 197.2

99.0 1.0

0 8

52 99.6 1.4850

48

54.7 1.4198 0.7523

98.3 106.1 109.4 112.2 115.6 119.4 122.8 127.8 134.4 142.2 153.9 163.9 202.8

99.0 1.0

Example 8

In order to show the high selectivity of other γ-lactones as solvents for aromatics, a mixture from 35% mesitylene and 65% n-decane by shaking out once with angelicalactone and with y-valerolactone extracted. The extraction was used for comparison

Levulinic acid, which can be converted into these lactones. The solution attempts were carried out at 27 ° C. The table below and FIG. 3 summarize the results and show the superior solution behavior the lactones compared to the parent acid, if extracted to the same aromatic content in the raffinate became.

Comparison of the dissolving power with a single extraction with undiluted solvent at 27 ° C on a 35% mesitylene-65% n-decane mixture

° / o aromatics in the raffinate Solvents
Angelicalactone
CH ₃ -C CH
! i
O CH ₂
C.
II
O Narrow, volume percentage of the coal
y-valerolactone
CH ₃ —CH— CH ₂
I!
O CH ₂
C.
O cassstoffgoods
Levulinic acid
CH ₃ CO (CH ₂ ) _a COOH 17th
25th 150
85 150 600
85 I 250

809 750/452

Claims (7)

Patent claims: 1. A method for breaking down petroleum into its more aromatic and more paraffinic constituents, characterized in that the petroleum is treated at about 10 to 260 ° C with preferably 100 to 300 percent by volume of a lactone, based on the oil, and the solvent extract phase obtained separates from the raffinate phase. 2. The method according to claim 1, characterized in that the lactone used is γ-butyrolactone. 3. The method according to claim 1 or 2, characterized in that a hydroformed gasoline, in particular the C _e ⁺ fraction thereof, is treated at about 10 to 150 ° C with the lactone. 4. The method according to claim 1 or 2 for the treatment of oils with a boiling range of about 204 to 704 ° C, characterized in that the gas oil fraction of a crude oil, including the portions boiling above 510 ° C, is treated with 50 to 300 percent by volume of lactone. 5. The method according to claim 1, characterized by with the use of solubility regulators, such as water, water-soluble aliphatic alcohols, acetic acid or ethylene glycol. 6. The method according to claim 1 or 2, characterized in that high-boiling gas oil components including those boiling from 510 to 704 ° C are treated with a lactone. 7. The method according to claim 1 or 2 for the production of high quality lubricating oils from a lubricating oil distillate in the boiling range of about 370 to 595 ° C, characterized in that the oil is treated with 100 to 300 percent by volume of butyrolactone and a raffinate oil with a better viscosity index is separated. Considered publications: Ellis, The Chemistry of Petroleum Derivatives, 1937, Vol. II, p. 169; U.S. Patent No. 2,063,680. 1 sheet of drawings © 809 750/452 2.